You will need to cooked the sweet potatoes and mash them first, unless you have some on hand. I chose to peel, chop, and boil the potatoes until they were tender. Then mash them and allow to cool to room temp.
Preheat oven to 350 degrees. Butter and flour a 9x5 inch loaf pan. Set aside.
In a small bowl, combine the cranberries and pecans with 2 tablespoons of the flour (from the 1 1/2 cups). Toss to coat the fruit and nuts. Set aside.
In a large bowl, whisk together the remaining flour (1 cup plus 6 tablespoons), baking powder, salt, brown sugar, cinnamon, nutmeg, and ginger. Make a well in the center of the dry ingredients. Add the cooled mashed sweet potatoes, beaten eggs, milk, and melted butter. Using a wooden spoon, combine all the ingredients until just mixed.
Gently fold in the cranberries and pecans.
Pour the batter evenly into the prepared loaf pan. Bake for 50-60 minutes, or until a toothpick inserted in the center comes out clean. Allow bread to cool in pan a few minutes before removing to a wire rack to cool a bit more.